'FN' (i) was the designation of British coastal convoys (together with a numerical suffix) plying from Southend on the Thames estuary to Methil on the Firth of Forth, and as such reciprocals of the 'FS' series (September 1939/June 1945).

The route was protected by defensive minefields, but was vulnerable to attack by U-boats, S-boote, aircraft and mines.

These 'Forth North' convoys were numbered from 1 to 100 in repeating phases, and the first of these 1,660 convoys was FN.1 of 8/9 September 1940 with 20 merchant vessels, and the last was FN.22 (seventh series) of 31 May/1 June 1945 with the 764-ton Belgian Anna, 6,854-ton British Empire Moonrise, 3,139-ton British Enseigne Marie St Germain, 1,333-ton Norwegian Harpefjell, 1,289-ton Norwegian Jernland and 7,077-ton Norwegian Tai Yin.